1. Field of the Invention
The present disclosure relates to a digital protective relay, and particularly, to a ground configuration of a printed circuit board of a digital protective relay.
2. Background of the Invention
A digital protective relay refers to a relay for preventing the spreading of an electric accident by operating a circuit breaker when a fault current is detected in an electric power system. For instance, in a case where an electric accident such as a short circuit or an eddy current occurs on an electric circuit, the digital protective relay may control the circuit breaker to break the circuit where the accident has occurred, not to spread the electric accident.
In the conventional art, a printed circuit board (PCB) is grounded by installing a pin shaped contactor contactable to an enclosure at a guide rail of the PCB. However, such conventional grounding method has a problem that the enclosure of the digital protective relay should be formed of a metallic conductor.
As another conventional grounding method, there is a grounding method using a power supply module without forming a circuit pattern toward the ground on a printed circuit board. However, such method has a problem that grounding efficiency is lowered.